Exposure device

Abstract

The exposure device is especially intended for use with the contact print of circuit patterns on printed circuit boards, and is composed of a tubular light source extending with the length thereof throughout the exposure field width and disposed in a housing light-permeable over the exposure field, with the light source being disposed within a reflector open toward the exposure field and a light-directing grid covered by the side flanks of the reflector being located underneath the light source, and a heat insulating plate being provided underneath the light directing grid. An occulting strip (5) is disposed between the light source (1) movable across the exposure field and the light directing grid (4), and the reflector (3) is provided with an air exhausting slit (6) extending throughout the entire length thereof, with the housing (8) provided with at least one air inlet port (7) and enclosing the reflector forming the outer part of a ventilation channel guided about the reflector (3) and guided through the reflector.

What we claim is: 
     
       1. An exposure device, especially for the contact print of circuit patterns on printed circuit boards, composed of a tubular light source extending with the length thereof throughout the entire exposure field width and disposed in a housing light-permeable over the exposure field, with the light source being disposed within a reflector open toward the exposure field and a light-directing grid covered by the lateral flanks of the reflector being located underneath the light source and a heat insulating plate being provided underneath the light directing grid, characterized in that an occulting strip (5) is disposed between the light source (1) movable across the exposure field and the light-directing grid, and the reflector (3) is provided with an air exhausting slit (6) extending throughout the entire length thereof, with the housing (8) provided with at least one air inlet port (7) and enclosing the reflector forming the outer part of a ventilation channel guided about reflector (3) and guided through the reflector.   
     
     
       2. A device according to claim 1, characterized in that the occulting strip (5) is of a hollow formation and is provided with connections for passing a coolant therethrough. 
     
     
       3. A device according to claim 1, characterized in that the occulting strip (5) is formed as a mirroring prism and so disposed that the incident heat radiation is reflected on the outer wall of the reflector. 
     
     
       4. A device according to claim 1, characterized in that the air exhausting slit (6) and the at least one air inlet port (7) of housing (8) is provided with air carrying conduits (10), and the latter are connected, at the suction or pressure sides, to a space independent of reflector (3). 
     
     
       5. A device according to claim 1, characterized in that the at least one air inlet port (7) of housing (8) is disposed above the reflector (3). 
     
     
       6. A device according to claim 1, characterized in that the light source (1) including reflector (3) and light-directing grid (4) is configured and disposed to be movable into at least one end position externally of the heat insulating plate (9). 
     
     
       7. A device according to claim 1, characterized in that the light source (1) with reflector (3) and light-directing grid (4) along with housing (8) enclosing the said elements are disposed to be movable relative to the exposure field (2). 
     
     
       8. A device according to claim 1, characterized in that the light source (1) with reflector (3) and light-directing grid (4) is movably disposed within a stationary housing (8) covering the whole of the exposure field (2). 
     
     
       9. A device according to claim 1, characterized in that the reflector (3) is disposed in a carrier (12) of heat conductive material conforming in shape to the reflector and, on the outer side, is provided with heat exchanging surface enlargements (13), such as cooling ribs or the like.